Question

question 2
1 pts
an atom that has gained or lost one or more electrons is the definition of an:
element
molecule
ion
isotope

question 3
1 pts
the earths atmosphere is mostly nitrogen. is the
itrogen\ in this statement referring to the element or the atom?
atom
element

Explanation:

For Question 2, an ion is an atom that has gained or lost one or more electrons. An element is a pure substance made of only one type of atom, a molecule is a group of atoms bonded together, and an isotope is an atom of an element with a different number of neutrons.
For Question 3, when we say the Earth's atmosphere is mostly nitrogen, we are referring to the element nitrogen which exists in the atmosphere mainly as nitrogen - containing compounds or as $N_2$ molecules, not just individual nitrogen atoms.

Answer:

Question 2: C. ion
Question 3: B. element